1. Field of the Invention
The present invention relates to a disk loading apparatus for moving a disk cartridge between an ejection/insertion position and a loading position, said cartridge containing a data recording disk such as an optical disk or an optomagnetic disk. The disk loading apparatus is designed for use in a disk drive to recording data on a data recording disk and reproducing data therefrom.
2. Description of the Related Art
The disk loading apparatus can move the disk cartridge from the ejection/insertion position to the loading position, and vice versa, while holding the cartridge by means of a cartridge holder. At the ejection/insertion position, the cartridge can be inserted into, and ejected from, a slot made in one side of the housing of the disk drive. At the loading position within the housing of the disk drive, the data recording disk (hereinafter called "disk") is placed on the turntable connected to the spindle motor located in the housing. The disk loading apparatus can move the disk cartridge from the ejection/insertion position to the loading position, and vice versa, while holding the cartridge by means of a cartridge holder.
A disk loading apparatus of this type is disclosed in, for example, Jpn. Pat. Appln. KOKAI Publication No. 4-67461. This apparatus (hereinafter referred to as "first conventional apparatus") comprises a control lever. The control lever applies a pressure onto a side of a disk cartridge while the cartridge is being ejected from a disk drive, thereby preventing the cartridge from falling from the cartridge slot made in a side of the disk drive.
The first conventional apparatus further comprises a mechanism for stop applying the pressure onto the side of the disk cartridge. The mechanism has a detection lever which can rotate around at its one end, for detecting whether or not a disk cartridge is being inserted into the disk drive through the cartridge slot. When the cartridge is inserted into the disk drive to a predetermined depth, the detection lever contacts, at its abutting side, a pin protruding from the control lever. The detection lever therefore rotates the control lever away from the side of the disk cartridge, overcoming a bias for pushing the control lever onto the side of the cartridge. Thus, the control lever is separated from the side of the cartridge.
The first conventional apparatus is, however, disadvantageous in the following respects.
(1) Since the detection lever only rotates around its one end, the lever is unable to move along a straight line, the apparatus cannot be as thin as a disk loading apparatus (hereinafter referred to as "second conventional apparatus") disclosed in Jpn. Pat. Appln. KOKAI Publication No. 4-186554. In the second conventional apparatus, the detection lever not only rotate around its one end but also move along a straight line, thereby apply a pressure onto the side of a disk cartridge and also to open and close the shutter of the cartridge.
(2) The abutting side of the detection lever may fail to smoothly contact the pin of the control lever due to the dust accumulated on the contact side or the running out of lubricating oil. If this happens, the bias applied on the control lever is not sufficient enough to eject the disk cartridge from the disk drive.
(3) Since the bias on the control lever is suddenly applied to the detection lever when the pin of the control lever abuts the abutting side of the detection lever. Consequently, the pressure on the cartridge by the control lever increases or decreases abruptly, making smooth insertion or ejection of the cartridge impossible.
Another disk loading apparatus is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 4-137256. The apparatus (hereinafter referred to as "third conventional apparatus") has an opening/closing arm. The arm is designed to eject a disk cartridge from a disk drive and also to open and close the shutter of the cartridge. The arm is set in engagement with a damper, which helps the arm to move smoothly such that the cartridge is prevented from jumping from the cartridge slot of the disk drive.
Still another disk loading apparatus is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 4-168673. The apparatus (hereinafter referred to as "fourth conventional apparatus") has a drive plate for moving a cartridge holder between an ejection/insertion position and a loading position and, to thereby move a disk cartridge between these two positions. The drive plate is always biased toward the ejection/insertion position and placed in engagement with a rotary damper. Engaged with the rotary damper, the drive plate reduces the speed at which the disk is moved relative to a turntable as it is mounted onto the turntable. This minimizes the impact which disk and the spindle motor connected to the turntable exert to each other and, ultimately, servers to enhance the durability of the apparatus.
A disk loading apparatus is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 4-109487. The apparatus (hereinafter referred to as "fifth conventional apparatus") comprises a shutter for opening and closing the cartridge slot made in one side of the housing of a disk drive. The shutter is rotatably supported between the slot-opening direction and the slot-closing direction. The fifth conventional apparatus further comprises a spring stretched between the shutter and the wall of the housing. This spring urges the shutter to the slot-closing position.
The third to fifth conventional apparatuses, how ever, need some improvement to be put to practical use.